RU2065612C1 - Position-indicating receiver - Google Patents

Abstract

FIELD: radio navigation; position indication of movable objects. SUBSTANCE: device has receiver 1, search and additional search unit 2, N tracking units 3, multiple-value enabling unit 4, reference and control signal shaping unit 5, control console 6, reference oscillator 7, switching unit 8, radionavigation parameter measuring unit 9, hyperbolic coordinates converter 10, indicator 11, correction input unit 12, buffer register 13, parameter computing unit 14, threshold unit 15, decision taking unit 16, working station selecting unit 17; all of them enable using additional information from all stations of system present in input signal. If coordinates obtained do not differ by more than measurement error value of phasal tracking system, decision is made about correct enabling of multiple-valued readings. Otherwise, readings are corrected for each separate station. EFFECT: provision for receiving information from all stations of system present in input signal and using additional information. 11 dwg

Description

 The invention relates to radio navigation and may find application in determining the location of moving objects.

Known aircraft system 0 1-7000 (1), in which the choice of the optimal triples of the station is made using a complex model of signal propagation, which includes a detailed account of the conductivity map of the underlying layer. Based on the known position of the aircraft recorded in the computer memory, pre-entered data on the coordinates and radiated power of the Laurent-S station and the specified signal propagation model, the optimal one from the point of view of the maximum signal level of the station three is selected. Many modern on-board devices of the Laurent-S system are based on the structure of the radio navigation coordinator (2), selected as a prototype. The operation of the prototype device is as follows in accordance with figure 1. The signals of the station after the matched filtering in the receiver 1 are sent to the search and additional search unit 2, where the search is first performed (determination of the temporary position accurate to the signal duration), and then additional search (determination of the edge position) of the station signals. Tracking blocks 3 (their number is equal to the number of stations) determine the moment of passage through zero of the carrier signal of stations with a specific derivative (phase measurement of the signal position). Using block 4 resolving ambiguity provides the elimination of ambiguity of phase samples. Unit 9 measuring the radio navigation parameter provides hyperbolic coordinates of the location of the object, according to which the coordinate converter 10 calculates the location coordinates in a more convenient coordinate system. The calculated coordinates are displayed on the indicator 11. Block 5 formation of the reference and control signals provides the formation of time diagrams of pulsed reference sequences and signals. The control unit 6 sets the necessary parameters (repetition period, phase code, etc.) of the station signals, and the reference oscillator 7 generates a highly stable sinusoidal signal necessary for coherent signal processing. A disadvantage of the known device is the low accuracy of positioning due to a decrease in the reliability of the resolution of the ambiguity of phase readings. The technical result of using the invention is to increase the accuracy of positioning by increasing the reliability of the resolution of the ambiguity of phase readings. The essence of the invention is to use additional information from the remaining stations of the system present in the input signal. If there is redundant information about the position of a moving object, it is possible to determine the presence of an error in the resolution of ambiguity by one of the stations, the number of the station with an erroneous resolution of ambiguity, and the magnitude of the error. The block diagram of the receiver is shown in figure 2. The structure of the switching unit 8, the input unit of amendments 12, the threshold unit 15 are shown respectively in FIG. 3-5, the algorithms of the decision block 16, the selection block of workstations 17 are presented in FIGS. 6-9, explaining the graphic materials in FIG. 10, 11. In Fig.1-5 indicated:
1 receiver (PFP), 2 search and additional search (BPD) block, 3 tracking units (BS), 4 ambiguity resolution block (BRM), 5 block for generating reference and control signals (BFOUS), 6 control panel, 7 reference generator, 8 switching unit (BC), 9 unit for measuring the radio navigation parameter (BIRNP), 10 converter for hyperbolic coordinates (PC), 12 input for corrections (BWP), 13 buffer register (BR), 14 unit for calculating the parameter (BWP), 15 threshold unit ( PB), 16 decision making unit (BPR), 17 workstation selection unit (BVRS), 18, 19, 20 multiplexer (MP), 21, 22, 23 - arithmetic -logic device (ALU), 24,25,26 decoder (DSH), 27 - arithmetic-logic device (ALU), 11 indicator (IND). The operation of the coordinator is as follows. The signals of the pulse-phase radio navigation systems (IFRNS) are fed to the input of the receiver 1, where a coordinated filtering of each pulse from the packet of IFRNS signals and their amplification is carried out. In block 2 of the search and additional search, the filtered IFRNS signals are extremely limited (i.e., they are binary quantized in amplitude), are gated in time, and phase decoded. The received signal are summed in each quantization time interval during the accumulation time. The accumulation results are compared with a threshold. If the threshold is exceeded, a decision is made about the presence of a signal in the corresponding time interval. Otherwise, the whole process is repeated. The signal from the output of the receiver 1 also goes to the inputs of the tracking units 3, each of which is a tracking system for the phase of the binary quantized signal of the IFRNS. The latter is fed to a discriminator with a relay characteristic, the error signal from the output of which is averaged and fed to the command output of the tracking unit 3. In the tracking blocks 3, the first of the packet of tracking gates is also allocated, which is fed to the output of the tracking blocks 3. Each tracking block 3 measures the phase of the signal of one of the IFRNS stations. In the ambiguity resolution block 4, the signal of the receiver 1 is subjected to high-frequency differentiation, as a result of which a radio pulse is generated. The point of passage through zero with the negative derivative of the envelope of this radio pulse is located at a given point of the IFRNS pulse signal. The averaged error signal of the tracking system is fed to the output of the ambiguity resolution block 4. When the tracking gate is installed at the point of passage through zero of the envelope, the corresponding signal appears at the output of the ambiguity resolution block 4. Block 5 of the formation of the reference and control signals controls the operating mode of the receiver and generates the necessary control signals in each mode.

 Operation mode control is provided by software. To do this, when you turn on the power of the receiver-coordinator, the program is set to its initial state corresponding to the mode of searching for IFRNS signals. When a master station signal is detected by the search and additional unit 2, a signal appears at the command input of block 5, which ensures that the unit 5 transfers the receiver to the search mode of the master signals. If the leading station signal is not detected from the output of the search and additional search unit 2, a signal will appear that, having arrived at the command input of the BFOUS block 5, the search gates will malfunction by the value of the search interval. The lead station search mode will continue on a new interval of the IFRNS signal repetition period. Similarly, the operation of block 5 occurs during the search and additional search for signals of other IFRNS stations. After completing the additional search for signals of all stations, block 5 will put the receiver-coordinator into measurement mode. In this mode, signals indicating the completion or non-completion of the ambiguity resolution for each station are received from the output of the ambiguity resolution block 4 to the second control input of block 5. Upon completion of the ambiguity resolution for all IFRNS stations, block 5 generates a signal providing the resolution of operation of the radio navigation parameter measurement block 9 . Block 5 also generates reference signals for gating IFRNS signals. The reference signals are generated by dividing the voltage frequency from the reference generator 7. The repetition period of the reference signals sets the signal from block 6. The timing diagram of the reference signals for each station is determined by the mode of operation of the receiving coordinator (search, additional search, measurement), which is set by block 5. The formation of the temporary diagrams of the reference signals of each IFRNS station can be shifted by the value of the voltage period of the reference generator 7 under the action of a signal from the command output of the corresponding tracking unit 3 That provides tracking phase IFRNS signals. The signal from the output of the tracking system for the period of high-frequency filling from the ambiguity resolution block 4 can shift the beginning of the formation of the timing diagram of the reference signals by the value of the period of the carrier of the IFRNS signals.

 The switching unit 8 passes to its output the tracking strobes of the selected station three. The gates themselves are fed to the signal inputs of the 18-20 multiplexers from the BSZ outputs, and the code of the selected station three from BV 17 is received at their control inputs. The BIRP unit 9 determines the time delay of the first of the packet of tracking gates coming from the outputs of the blocks 3 of the tracking of the selected three of the IFRNS stations , relative to the start of the repetition period of the timing diagram of the reference signals. The signals of the radio navigation parameter from BIRNP 9 are fed to the first signal input of the corresponding ALU 21-23 of the correction input unit 12. The latter, under the influence of the signals at their control inputs, can pass signals from the first signal input to the output either unchanged, or increased by 10 μs, or reduced by 10 μs. The corresponding control signal for selecting the operation comes from the decoders 24-26, which form it from the BPR signal 16. The signals of the radio navigation parameter from the output of the correction input unit 12 are fed to the input of the PGA 10, where the hyperbolic coordinates given by the IFRNS station three unit 17 are converted into coordinates convenient for positioning , for example, rectangular. BR 13 stores the signal converted to PGC 10 at the time the decision is made in BPR 16. These coordinates are displayed on the indicator 11. The information change signal in BR 13 is supplied to its control input from block 17 after a decision is made in block 16 about the correct completion of ambiguity. The calculation unit of parameter 14 determines the size of the figure S (for example, the perimeter). For this, the coordinates of all triples of the station obtained from block 10 are stored in it, the search of which, like the control of block 14, is ensured by the selection block of workstations 17. The perimeter of the figure is determined from the coordinates of the vertices using relations known from mathematics. The signal from the output of block 14 is fed to the first signal input of ALU 27 in block 15, and the signal corresponding to the threshold is supplied to the second signal input of ALU 27. The control input to the ALU 27 receives a control signal to implement either the subtraction function or broadcast the signal from the first signal input to the output of the ALK 27. The decision block 16 starts with the initial settings of the control signals, correction selection signals and command signals. Moreover, the control signals are supplied respectively to decoders 24-26 in block 12, the correction selection signals determine the selection of corrections, respectively, at IFRNS stations 0,1,2,4 (condition 0 means no correction, (1 addition of the correction in 10 μs, 2 subtraction of the correction in 10 μs, assigning a value of 1 allows further operation of block 17.) Then, block 16 will wait for the figure size calculation to complete for the given initial conditions.After calculating the size of the figure, it will check the signal sign at the output of block 15. If the signal is negative, it is assigned with the corresponding sign and the operation of block 16. Otherwise, the search for the station begins with the erroneous completion of the ambiguity resolution and correction of the error value.This process begins with the assignment of the corresponding sign and waiting for the block 15 to switch to transmitting signals from block 14 under the action of the control signal from block 17 block 15. In block 16, the perimeter of figure S is stored at the initial values of the corrections and a new value of corrections is assigned at station 0. The block allows you to ensure the standby mode in block 16 and the operation of block 17. If preparation is being made for calculating the figure parameter value for new correction values, then in block 16 it is waiting for the code of the new triple of the IFRNS station to be set from block 17 to block 8. After this process is completed, the value will be set to 1. B in this case, for each station currently assigned to the trio, block 16 will ensure that the current value of corrections is issued to block 12. After enumerating all the possible values of the corrections, block 16 will restore the original value of the corrections and will form a sign of the end of the operation of enumerating the corrections. After that, block 16 organizes a census of the correction values for the minimum perimeter of the figure S in the operational memory cells. At block 12, control correction signals are issued that correspond to a figure with a minimum perimeter. This completes the algorithm of operation of block 16. In block 17, the polysemy resolution block 4 is interrogated to determine the number of stations for which the resolution of the ambiguity of phase readings has occurred. In block 17 signs are summarized for all IFRNS stations. Next, a block 6 is polled to find out the operator triple of the IFRNS station set by the operator and the possibility or impossibility of station determination or the presence of redundant information is checked. In block 17, the expectation of the appearance of the resolution of the ambiguity of the remaining stations is ensured, the radio navigation parameter is measured, the rectangular coordinates are calculated for the station triple selected in block 6, and these coordinates are entered for storage in the buffer register 13.T.O. the operation of the proposed device is similar to the operation of the prototype device in the absence of redundant information. When the number of stations is more than three, block 17 will set a threshold subtraction control signal on block 15, set the parameters of the initial analyzed triple of the station according to which the radio navigation parameter will be calculated by applying the corresponding control signal to block 8. Block 17 also enables the coordinate converter 10 to work and store the calculated coordinates in block 14. In block 17, sorting out all possible triples of the IFRNS station is organized, after which a control signal will be sent to block 14 to conducting calculation of the perimeter of the figure. The sign of the verification result generated in decision block 16 will be analyzed in block 17. If the necessary conditions are met, the coordinates will be given to block 13 for the assigned IFRNS station three. Otherwise, block 17 will set the information transmission control signal on block 15. If the enumeration of amendments in block 16 is not completed, then work 17 will be repeated in this part; if the enumeration of amendments is completed, then block 17 for the IFRNS station assigned in block 6 will allow you to set the necessary corrections to block 12 and display the location coordinates with the corrected ambiguity resolution results phase readings.

 Thus, the introduction of a switching unit 8, an amendment input unit 12, a buffer register 13, a parameter calculation unit 14, a threshold unit 15, a decision unit 16, a selection unit of the workstations 17 and their connection to the prototype device allows to increase the accuracy of positioning by increasing the reliability resolving the ambiguity of phase samples.

Used literature:
1. Marshal L.U. Francis B.O. Aircraft system 0 1-7000 LORAN-S.

 2. Lutchenko A.E. Coherent reception of radio navigation signals. M. "Sov. Radio", 1973, pp. 52-53, Fig. 3.1.3.2 (prototype). YYY2 YYY4 YYY6 YYY8 YYY10

Claims (1)

 A receiving coordinator comprising a receiver, the output of which is connected to the inputs of the search and search units, tracking and polysemy resolution, the output of the search and search unit is connected to the command input of the reference and control signal generation unit, the output of which is connected to the control inputs of the search and additional search, tracking and block units ambiguity resolution, the output of which is connected to the command outputs of the tracking units and the second control input of the block for generating the reference and control signals, the first control input of which connected to the output of the control panel, and the signal input to the output of the reference generator, as well as containing a block for measuring the radio navigation parameter, a converter of hyperbolic coordinates and an indicator, the control input of the measuring block for the radio navigation parameter is connected to the output of the block for generating the reference and control signals, characterized in that the block is introduced switching, corrections input block, buffer register, parameter calculation block, threshold block, decision block and workstation selection block, and outputs b tracking channels are connected to the corresponding inputs of the switching unit, the output of which is connected to the input of the measuring unit of the radio navigation parameter, the output of which is connected to the input of the correction input unit, the output of which is connected to the input of the converter of hyperbolic coordinates, the output of the converter of hyperbolic coordinates through the buffer register is connected to the indicator input, the output the hyperbolic coordinate transformer is also connected to the input of the parameter calculation unit, the output of which through series-connected an ocov block, a decision block and a workstation selection block are connected to a control input of a switching block, the control inputs of a hyperbolic coordinate converter, a parameter calculation block, a buffer register, a threshold block and a decision block being connected to the output of a workstation selection block, the control input of which is connected with the output of the control panel, and the command input with the output of the ambiguity resolution block, the output of the decision block is connected to the control input of the correction input block.

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